As power presses have continued to increase in size and capacity, the components of such presses have also increased both in size and weight, and are now so large and unwieldy that much time and energy must be expended when removal of these components is required. In order to reduce both the amount of down time for such a large press and also the cost of labor of the highly paid press workers during the changeover, manufacturers have long sought to simplify changeover procedures.
An exemplary and early innovation of this type is shown in Vasil Georgeff, U.S. Pat. No. 3,111,100, issued November 19, 1963, which was assigned to the assignee of the present invention. The Georgeff patent, entitled "Quick Die Change Press," solved an industry-wide dilemma providing the manufacturer with a power press wherein the press dies were changeable in a rapid, convenient, and expeditious manner. As a result of that improvement, press versatility and efficiency was substantially increased, while the excessively high labor costs incurred in changing the dies were significantly reduced.
In the disassembly of a power press, one of the most difficult and time consuming operations which must be performed is the removal of the slide mechanism for maintenance or repair. In a typical double action press there are two slide mechanisms, an inner slide and an outer slide or blankholder, these slide mechanisms are of such construction that they cannot normally be removed through the press uprights. Accordingly, the labor costs associated with this removal procedure are quite high, and due to the size and weight of the slide mechanisms, considerable precautions are necessary so as not to expose workers to significant danger.
In a conventional underdrive press, the pull rods connect directly to a connecting adjusting mechanism mounted on the upper surface of the slide below the crown. Typically, the crown is of considerable size and weight and is located at a substantial distance above the pressroom floor. Accordingly, the use of an overhead crane is required in order to perform the changeover procedure. And, since the slide mechanisms cannot be simply removed through the press uprights, the crane must also be used to lift the slide mechanism out from between the uprights. Such a method of slide removal results in excessive down time and cost, and potentially poses dangers within the pressroom.
Furthermore, conventional double action presses are designed such that the inner slide is guided within the blankholder. Accordingly, removal of the slides first requires disconnecting the pull rods and then lifting the slides from between the uprights. In conventional presses, the pull rods and crossheads are disposed within the press uprights, and due to the requirement that the inner slide be guided within the blankholder, the pull rods and crossheads occupy a substantial portion of the upright interior. Presses have not been heretofore constructed where a press has allowed for the removal of an assembled slide mechanism through the uprights.
Accordingly, it is an object of the present invention to provide a power press wherein the slides are transversely removable through the uprights without requiring disassembly of the press frame or slide mechanisms.
Furthermore, it is an object of the present invention to provide a power press wherein the inner slide and blankholder are independently guided by fully adjustable gibbing on the press uprights.
It is a further object of the invention to provide improved means for removing the slides from the frame of an underdrive press.
Yet another object of the invention is to provide a power press wherein the slides may be removed in a safe, expeditious and efficient manner.